function getFormatDate(timestamp) {
  timestamp = parseInt(timestamp);
  if (!timestamp) {
    return;
  }
  var newDate = new Date(timestamp);
  Date.prototype.format = function (format) {
    var date = {
      'M+': this.getMonth() + 1,
      'd+': this.getDate(),
      'h+': this.getHours(),
      'm+': this.getMinutes(),
      's+': this.getSeconds(),
      'q+': Math.floor((this.getMonth() + 3) / 3),
      'S+': this.getMilliseconds()
    };
    if (/(y+)/i.test(format)) {
      format = format.replace(RegExp.$1, (this.getFullYear() + '').substr(4 - RegExp.$1.length));
    }
    for (var k in date) {
      if (new RegExp('(' + k + ')').test(format)) {
        format = format.replace(RegExp.$1, RegExp.$1.length == 1
          ? date[k] : ('00' + date[k]).substr(('' + date[k]).length));
      }
    }
    return format;
  }
  return newDate.format('yyyy-MM-dd');
}

module.exports = {
  getFormatDate: getFormatDate
}